FIG. 1 is a schematic block diagram of a conventional recording system 100 and an optical recording medium 112. Data 102 from the data source 104 are encoded by an eight-fourteen-modulation (EFM) encoder 106 to generate EFM encoded data. The encoded data are then transformed into write-strategy data by a write-strategy (WSR) unit 108 and transmitted to an optical pick-up (OPU) 110. Finally, the OPU 110 emits laser power onto an optical recording medium 108 according to the write-strategy data, and then forms a land/pit profile on the optical recording medium 112 via control circuit 114.
FIG. 2 is a schematic timing diagram of a conventional recording process performed by the recording system 100 in FIG. 1. When data 102 and target starting position 200 on the disk address are ready, the OPU 110 is controlled to seek the front of the target starting position 200 and perform a tracking and following procedure to track the target starting position 200 during an OPU action. The record-initialized functions are actuated during the period 202 and target-search criterion need to be taken during the period 204. When reaching the target starting position 200, the OPU 110 emits light to write the data 102 onto the optical recording medium 112 according to a writing signal. That is, a latency period 206 to start the recording process on the recording medium 112 is the sum of period 202 and the period 204.
According to the above description, the data 102 that are transformed into the write-strategy data will be written onto a section of the optical recording medium 112. While the section has some areas that are not desired to be recorded, the recording system 100 has to divide the data 102 into several parts to part-record the desired areas. However, when the recording system 100 performs the part-recording process to pass the undesired recording areas, there are some drawbacks.
The first drawback: when the two adjacent desired areas (300, 302) are too close so that the recording system 100 cannot track the next starting position 200, the recording system 100 wastefully has to seek a proper position to let the OPU 110 track on the next starting position 200. As shown in FIG. 3A, it is a schematic timing diagram of conventional part-recording process performed by the recording system 100 in FIG. 1. When the two adjacent areas (300, 302) are too close, it is necessary to reserve enough latency period 206 for performing seeking, tracking and following procedures on the disk address to track the next starting position 200 during the OPU action. However, the sum of period 202 and target-search criterion period 204 is smaller than the required latency period 206 in the writing procedure. As a result, these procedures are repeatedly performed, resulting in efficiency decrement of the recording system 100.
The second drawback: even when the two desired areas (300, 302) are far enough for the recording system 100 to track on the next starting position 200, the recording system 100 still cannot meet the criteria to start next recording 200 because the poor quality 306 of the optical recording medium 112 or the unreliable detection 308 of the disk address during the tracking and following procedures. Referring to FIGS. 3B and 3C, they are schematic timing diagrams of conventional part-recording process performed by the recording system 100 in FIG. 1 when the quality of the optical recording medium 112 is poor 306 or the detection of the physical address 308 on the disk address is unreliable during the writing procedure. In FIG. 3B, the OPU 110 cannot find the next starting position 200 during target-found 310 even if the sum of period 202 and target-search criterion period 204 is greater than the required latency period 206. Therefore, the writing procedure of the recording system 100 fails. Further, the recording system 100 must further perform several seeking steps, including target-search criterion periods 204, to move the OPU 110 a distance, which causes much more latency and cannot actuate the writing signal 312 and the writing procedure 314, as shown in FIG. 3C.
In conventional Digital Versatile Disk Random Access Memory (DVD-RAM), when data are recorded in sectors of the optical recording medium, header in the Complementary Allocated Pit Addressing (CAPA) area would be skipped. However, the header does not correspond to the writing signal of the write-strategy unit 108 due to a skip. Further, the header cannot be addressed by the control circuit. Therefore, the header information cannot be written on the optical recording medium precisely. In addition, when data are recorded on the DVD-RAM, the defect areas in the Primary Defect List (PDL) are slipped and results in discontinuous recorded addresses. However, the writing signal corresponding to the discontinuous recorded addresses fail to be identified due to the slip.
Consequently, there is a need to develop a control system to solve the problems.